This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section. Abbreviations that may be found in the specification and/or the drawing figures are defined below at the end of the specification but prior to the claims.
In modern communication systems such as cellular systems, data to be transmitted is amplified prior to transmission. For instance, a base station in WCDMA/LTE/GSM radio access technologies (RATs) uses a power amplifier to amplify data prior to transmission. The power amplifiers in these base stations may produce average power during high traffic hours of 40-60 watts of RF power, with peak wattage ranging into the hundreds of watts for short durations during peak traffic hours.
During off-peak hours (e.g., when there is very little radio traffic demand), such as at night, the power amplifiers are transmitting very low power (e.g., 10-20 percent of average power), which are typically the control signals of the base station cell site. Even when the low power is being transmitted, the power amplifiers may burn, e.g., four to six watts of transmitted RF power and about 70-100 watts of DC power. For a single power amplifier, this does not sound like a large amount of power. However, the current trend, in order to keep up with data rate increases and especially for urban areas, is to install many smaller base stations. These smaller base stations vary in power, but are generally quite a bit smaller in power than a typical “macro” base station. Nonetheless, the off-hour power consumption of the smaller base stations and their associated power amplifiers is still significant, especially when DC power consumption is considered.
It would be beneficial to reduce the off-hour power consumption of power amplifiers and their corresponding base stations.